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351.
Conservation science deals with crises and supports policy interventions devised to mitigate highly uncertain threats that pose irreversible harm. When conventional policy tools, such as quantitative risk assessments, are insufficient, the precautionary principle provides a practical framework and range of robust heuristics. Yet, precaution is often resisted in many policy arenas, especially those involving powerful self-interests, and this resistance is compounded by structures of privilege and competitive individualism in science. We describe key drivers and effects of such resistance in conservation science. These include a loss of rigor under uncertainty, an erosion of crisis response capabilities, and a further reinforcement of privileged interests in conservation politics. We recommend open acknowledgement of the pressures exerted by power inside science; greater recognition for the value of the precautionary principle under uncertainty; deliberate measures to resist competitive individualism; support for blind review, open science, and data sharing; and a shift from hierarchical multidisciplinarity toward more egalitarian transdisciplinarity to accelerate advances in conservation science. Article impact statement: Precautionary principle, privilege structures among disciplines, and culture of individualism link to effective conservation policy making. 相似文献
352.
主要介绍了在国家外排粉尘浓度标准日益严格,普通电除尘器很难达标的背景下,提高电除尘器过滤效率的一种新技术软稳电除尘技术的原理和应用。 相似文献
353.
A significant number of pipeline operators use pipeline integrity management (PIM) to improve pipeline safety and reliability. Risk assessment is a critical step in PIM, because it determines the necessity of conducting the following steps in PIM for certain pipelines. Risk acceptance criteria are required in the process of risk assessment. Individual risk and societal risk are most frequently adopted as the two indicators of the risk acceptance criteria. To the best of the authors’ knowledge, quantitative societal risk acceptance criteria, especially for gas distribution pipelines, do not exit. The aim of this paper is to establish the societal risk acceptance criteria for gas distribution pipelines. Hence, FN curves were established using historical incident data from 2002 to 2017 provided by the U.S. Department of Transportation (DOT). Linear regression and the ALARP principle are used in evaluating the limits of the negligible line and intolerable line to obtain a graphical societal risk acceptance criterion for gas distribution pipelines. A line having a slope of −1.224, and an anchor point of (1, 8.413 × 10−7) is proposed as the negligible line. Further, the intolerable line has a slope of −1.224, and an anchor point of (1, 2.524 × 10−6). Both the negligible risk and the intolerable risk for the gas distribution pipeline are lower than the current societal risk acceptance criteria for hazardous installations. The reasons for these relatively lower risk acceptance criteria are discussed. 相似文献
354.
电子垃圾拆解地周边土壤中二(口恶)英和二(口恶)英类多氯联苯的浓度水平 总被引:3,自引:3,他引:0
采集了电子垃圾拆解地周边125个点位的151个土壤样品,分析了土壤中4~8氯代二噁英和二噁英类多氯联苯的浓度.表层土壤样品中总二噁英的浓度范围为280~7 010 pg·g-1,平均浓度为1 380 pg·g-1.中层和深层土壤样品中总二噁英的平均浓度分别为表土的63%和38%.表土样品中二噁英毒性当量浓度(以I-TEQ计)范围为1.4~94.8 pg·g-1.根据德国关于毒性当量浓度的指导方针,125个土壤样品中只有19个(15%)可以被认为对人体健康无害,其余85%的土壤需要调查二噁英的来源.如果考虑多氯联苯对毒性当量的贡献,则有98%的土壤需要调查二噁英的来源.主因子分析被用来调查这一地区二噁英的排放源.通过对土壤中二噁英的同系物分布进行分析,发现拆解活动是这一地区热过程二噁英的主要排放源,也是这一地区土壤中二噁英的主要来源. 相似文献
355.
基于LDI的土地利用类型与湿地水质的相关性:以苏州太湖三山岛国家湿地公园为例 总被引:1,自引:1,他引:0
以苏州太湖三山岛国家湿地公园为例,探索不同时空条件下土地利用类型整体与水质之间的相关关系.使用主成分分析计算出每个采样点的水质综合指数,基于GIS空间分析技术计算表征土地利用类型综合效应的景观开发强度指数(landscape development intensity,LDI),运用Pearson相关分析探讨水质与土地利用类型之间的整体相关性.结果表明,水质随着湿地公园空间分布不同而有较大的差异,研究区西部水质较好,东部水质较差;建设用地与水质综合指数存在明显的正相关,自然水体则与水质综合指数呈显著的负相关;缓冲区半径为100、150、200、250、300、350、400、450和500 m的LDI综合指数与水质综合指数的Pearson相关系数分别为0.641、0.678、0.691、0.685、0.691、0.695、0.680、0.653和0.649(P0.01),它们之间存在显著而稳定的相关性,可以体现出多种土地利用类型对湿地水质的整体影响,部分克服了单项土地利用类型表达不完整、难以解释水质变化的不足. 相似文献
356.
北京市某垃圾焚烧厂周边大气二(口恶)英污染特征及暴露风险 总被引:1,自引:0,他引:1
2014年4月至2015年1月对北京市某生活垃圾焚烧发电厂周边6 km范围内7个采样点采集环境空气,应用高分辨气相色谱-高分辨质谱(HRGC-HRMS)联用技术对二英(PCDD/Fs)浓度水平进行监测并对其组成特征及时空特征进行了分析.结果表明该生活垃圾焚烧发电厂周边环境空气中PCDD/Fs质量浓度的变化范围为8.9~140 pg·m-3,毒性当量(TEQ)变化范围为0.11~1.8 pg·m-3,其中秋季霾天4个采样点和冬季全部采样点超出日本环境空气质量标准限值(TEQ:0.6 pg·m-3).1,2,3,4,6,7,8-HpCDF和OCDD是四季空气中PCDD/Fs质量浓度的主要贡献单体,年平均贡献率分别为20.5%和14.0%,而2,3,4,7,8-PeCDF是总TEQ贡献最大的单体,年平均贡献率为43.3%.空间分布特征表现为各采样点浓度水平与距污染源距离远近没有显著相关性;季节变化特征表现为冬季值显著高于其他季节,分析可能与冬季燃煤采暖及大气扩散条件差导致的大气颗粒物污染较重有关,与各季采样时段内大气PM10和PM2.5的平均浓度水平呈正相关相一致.样品中二英同族体及异构体分布指纹谱图与该焚烧设施排放烟气存在差别,主成分分析(PCA)源解析结论与指纹谱图特征分析结论一致.二英呼吸暴露剂量估算结果表明该区域人群呼吸暴露风险总体处于较为安全的水平[0.060~0.224 pg·(kg·d)-1],但仍需关注大气颗粒物重污染天气发生时的呼吸暴露风险. 相似文献
357.
张维平 《防灾科技学院学报》2006,8(1):11-16
频发的突发公共事件造成的危机已经成为社会管理生活中不可避免的重大挑战,危机管理也就成为各国和各级政府都必须认真对待的重要问题,本文归纳了危机管理中应遵循的原则,运用的策略以及处理危机的过程。 相似文献
358.
Plant volatiles affect oviposition by codling moths 总被引:4,自引:0,他引:4
Peter Witzgall Lena Ansebo Zhihua Yang Gino Angeli Benoit Sauphanor Marie Bengtsson 《Chemoecology》2005,15(2):77-83
Summary. Oviposition in wild codling moth females, collected as overwintering larvae from apple, pear and walnut, was stimulated by volatiles from fruit-bearing green branches of these respective hostplants. Analysis of headspace collections showed that eight compounds present in apple, pear and walnut elicited a reliable antennal response in codling moth females: (E)--ocimene, 4,8-dimethyl-1,(E)3,7-nonatriene, (Z)3-hexenyl acetate, nonanal, -caryophyllene, germacrene D, (E,E)--farnesene, and methyl salicylate. Any one of these compounds is found in many other non-host plants, and host recognition in codling moth is thus likely encoded by a blend of volatiles. A large variation in the blend proportion of these compounds released from apple, pear and walnut suggests a considerable plasticity in the female response to host plant odours. Wild females, collected as overwintering larvae in the field, laid significantly fewer eggs in the absence of host plant volatiles. The offspring of these females, however, reared on a semi-artificial diet in the laboratory, laid as many eggs with or without plant volatile stimulus. Tests with individual females showed that this rapid change in oviposition behaviour may be explained by selection for females which oviposit in the absence of odour stimuli, rather than by preimaginal conditioning of insects when rearing them on semi-artificial diet. Oviposition bioassays using laboratory-reared females are therefore not suitable to identify the volatile compounds which stimulate egglaying in wild females. 相似文献
359.
在原有快速成形技术上进行改进,提出了一种新型快速原型制造技术———光热平面快速成形技术,对它的原理进行了系统的阐述,并分析了它在理论上的可行性以及实践上的难点所在。 相似文献
360.
排污权交易的经济优化机制研究 总被引:6,自引:0,他引:6
利用经济学原理,分析了环境污染产生的原因和经济学对策,对排污权交易理论和市场优化机制进行了研究,并说明我国建立排污权交易市场的可行性。 相似文献